In recent years and continuing, the copying machine is being developed into an imaging apparatus with multiple functions including scanner functions, facsimile functions, and printer functions, for example. Also, the copying machine may have various functions related to copying such as a color copying function and a stapling function, for example.
It is noted that the copying machine as is described above is usually stationed at a corporate office. A corporate office has its own employees as well as employees of other corporations tending to their daily businesses, and the copying machine may be used by many of these individuals.
In view of the fact that the copying machine is commonly used by many users, there is an increasing demand for user authentication techniques to perform access control and log record management, for example. Conventional user authentication methods usually require direct action from the user such as inputting a password, presenting an IC card, or providing fingerprint data, for example. However, authentication techniques have been developed that do not require such direct action from the user such as the user face authentication.
Japanese Laid-Open Patent Publication No. 2000-300828 discloses a technique involving use of a CCD camera to input face data of a user for performing user authentication. Japanese Laid-Open Patent Publication No. 2000-329945 discloses extending the application of the above disclosed technique to plural digital copying machines.
In the above cited documents, no disclosures are made with regard to the input timing of the user face data other than mentioning that “when a user is standing in front of the copying machine, a sensor detects the presence of the user”. However, it is noted that in a case where user authentication is not based on actions by the user that are consciously directed for authentication (e.g., presenting an IC card), it is quite important to determine the start timing of a user authentication process. According to the techniques disclosed in the above cited documents, the sensor may be activated even when a person is merely passing by the copying machine, and unnecessary authentication operations may be started, for example. Further, even in a case where the user is standing in front of the copying machine, the user may not necessarily be facing the camera when authentication operations are started, and image data required for face authentication may not be obtained. As a result, the authentication may end in failure, and an authentication failure event may be needlessly recorded in the log, for example.
Also, the disclosures of the above cited documents relate to a user authentication performed before a user operates the copying machine (login); however, no reference is made of logout operations performed after the user ends operation of the copying machine. It is noted that a user may be required to perform specific logout operations upon leaving the copying machine, or the user may simply leave the copying machine and automatic logout may be realized after no action is detected by the sensor for a predetermined period of time, for example. In the former case, user manipulations are increased and the user may possibly forget to execute the logout manipulations. In the latter case, another user may possibly approach the copying machine before the predetermined time period has elapsed and operate the copying machine as if he/she were the authenticated user, for example.